MeSH

Two-phase systems in which one is uniformly dispersed in another as particles small enough so they cannot be filtered or will not settle out. The dispersing or continuous phase or medium envelops the particles of the discontinuous phase. All three states of matter can form colloids among each other.

Particles consisting of aggregates of molecules held loosely together by secondary bonds. The surface of micelles are usually comprised of amphiphatic compounds that are oriented in a way that minimizes the energy of interaction between the micelle and its environment. Liquids that contain large numbers of suspended micelles are referred to as EMULSIONS.

Year introduced: 1991(1975)

Materials in intermediate state between solid and liquid.

Year introduced: 2006

used as markers in electron microscopy

Date introduced: November 19, 1986

Colloids with liquid continuous phase and solid dispersed phase; the term is used loosely also for solid-in-gas (AEROSOLS) and other colloidal systems; water-insoluble drugs may be given as suspensions.

Colloids with a solid continuous phase and liquid as the dispersed phase; gels may be unstable when, due to temperature or other cause, the solid phase liquefies; the resulting colloid is called a sol.

Colloids formed by the combination of two immiscible liquids such as oil and water. Lipid-in-water emulsions are usually liquid, like milk or lotion. Water-in-lipid emulsions tend to be creams. The formation of emulsions may be aided by amphiphatic molecules that surround one component of the system to form MICELLES.

Colloids with a gaseous dispersing phase and either liquid (fog) or solid (smoke) dispersed phase; used in fumigation or in inhalation therapy; may contain propellant agents.

Year introduced: was in Cat D & J 1973-1982, was in Cat D only 1963-1972